Interleukin‐10 inhibits cytokine generation from mast cells

Abstract
This report examines the effect of recombinant murine interleukin‐10 (rmIL‐10) on antigen‐induced β‐hexosaminidase, leukotriene (LT)C4 and cytokine release from mouse bone marrow‐derived mast cells (BMMC). BMMC sensitized to hapten‐monoclonal IgE directed against dinitrophenol‐bovine serum albumin (DNP‐BSA) and challenged with 10 ng/ml DNP‐BSA generated β‐hexosaminidase and LTC4‐like material, which was followed by tumor necrosis factor‐α (TNF‐α) and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) mRNA expression and protein release. Incubation of BMMC with 1–100 ng/ml rmIL‐10 inhibited cytokine generation, without affecting β‐hexosaminidase and LTC4‐like material release. TNF‐α, but not GM‐CSF mRNA expression, was also diminished in rmIL‐10‐treated BMMC, suggesting that down‐regulation of cytokine production by rmIL‐10 involves different mechanisms. These results identify a novel biological action of IL‐10 as an inhibitor of cytokine production by stimulated mast cells.